How To Install ngrep on CentOS 8

ngrep is Network layer grep tool

Introduction

In this tutorial we learn how to install ngrep on CentOS 8.

What is `ngrep`

ngrep strives to provide most of GNU grep’s common features, applying them to the network layer. ngrep is a pcap-aware tool that will allow you to specify extended regular or hexadecimal expressions to match against data payloads of packets. It currently recognizes TCP, UDP, ICMP, IGMP and Raw protocols across Ethernet, PPP, SLIP, FDDI, Token Ring, 802.11 and null interfaces, and understands bpf filter logic in the same fashion as more common packet sniffing tools, such as tcpdump and snoop.

We can use yum or dnf to install ngrep on CentOS 8. In this tutorial we discuss both methods but you only need to choose one of method to install ngrep.

Install ngrep on CentOS 8 Using dnf

Update yum database with dnf using the following command.

sudo dnf makecache --refresh

The output should look something like this:

CentOS Linux 8 - AppStream                                       43 kB/s | 4.3 kB     00:00    
CentOS Linux 8 - BaseOS                                          65 kB/s | 3.9 kB     00:00    
CentOS Linux 8 - ContinuousRelease                               43 kB/s | 3.0 kB     00:00    
CentOS Linux 8 - Extras                                          23 kB/s | 1.5 kB     00:00    
CentOS Linux 8 - FastTrack                                       40 kB/s | 3.0 kB     00:00    
CentOS Linux 8 - HighAvailability                                36 kB/s | 3.9 kB     00:00    
CentOS Linux 8 - Plus                                            24 kB/s | 1.5 kB     00:00    
CentOS Linux 8 - PowerTools                                      50 kB/s | 4.3 kB     00:00    
Extra Packages for Enterprise Linux Modular 8 - x86_64           13 kB/s | 9.2 kB     00:00    
Extra Packages for Enterprise Linux 8 - x86_64                   24 kB/s | 8.5 kB     00:00    
Metadata cache created.

After updating yum database, We can install ngrep using dnf by running the following command:

sudo dnf -y install ngrep

Install ngrep on CentOS 8 Using yum

Update yum database with yum using the following command.

sudo yum makecache --refresh

The output should look something like this:

CentOS Linux 8 - AppStream                                       43 kB/s | 4.3 kB     00:00    
CentOS Linux 8 - BaseOS                                          65 kB/s | 3.9 kB     00:00    
CentOS Linux 8 - ContinuousRelease                               43 kB/s | 3.0 kB     00:00    
CentOS Linux 8 - Extras                                          23 kB/s | 1.5 kB     00:00    
CentOS Linux 8 - FastTrack                                       40 kB/s | 3.0 kB     00:00    
CentOS Linux 8 - HighAvailability                                36 kB/s | 3.9 kB     00:00    
CentOS Linux 8 - Plus                                            24 kB/s | 1.5 kB     00:00    
CentOS Linux 8 - PowerTools                                      50 kB/s | 4.3 kB     00:00    
Extra Packages for Enterprise Linux Modular 8 - x86_64           13 kB/s | 9.2 kB     00:00    
Extra Packages for Enterprise Linux 8 - x86_64                   24 kB/s | 8.5 kB     00:00    
Metadata cache created.

After updating yum database, We can install ngrep using yum by running the following command:

sudo yum -y install ngrep

How To Uninstall ngrep on CentOS 8

To uninstall only the ngrep package we can use the following command:

sudo dnf remove ngrep

ngrep Package Contents on CentOS 8

/usr/lib/.build-id
/usr/lib/.build-id/23
/usr/lib/.build-id/23/c71df214bdf23c28f6658138c7037608ecbc68
/usr/sbin/ngrep
/usr/share/doc/ngrep
/usr/share/doc/ngrep/CHANGES
/usr/share/doc/ngrep/CREDITS
/usr/share/doc/ngrep/EXAMPLES.md
/usr/share/doc/ngrep/README.md
/usr/share/licenses/ngrep
/usr/share/licenses/ngrep/LICENSE
/usr/share/man/man8/ngrep.8.gz

References

ngrep website

Summary

In this tutorial we learn how to install ngrep on CentOS 8 using yum and dnf.